The Color Tournament
You must use 4 pokemon all of the same color out of red, blue, yellow, green, brown, orange purple, black and white. The staff makes a list which explicitly states which pokemon are classified as which color(You could even include shiny colorations). If they want, a pokemon can be multiple colors, but that really complicates the list. This list needs to be made, for pokemon with more than one color, such as electrode.
This would make for a tournament with fun teams and a similar premise to monotype, but allowing for much more interesting combinations.